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Accurate load modeling is essential for power system dynamic simulation. In this paper, four dynamic load models are identified based on multiple online measurement data from the Taiwan Power System. The performances in modeling real and reactive power behaviors by dynamic and selected static load models are evaluated. Parameter variation with respect to different loading conditions is analyzed. A simple and efficient method is presented to estimate a representative parameter set for different loading conditions. The cross-validation technique is applied to validate the four dynamic load models in order to obtain a better estimate of their performance. Numerical studies indicate that linear dynamic load models studied in this paper give better results than two nonlinear dynamic load models in modeling reactive power behaviors during disturbance while they are comparable in modeling real power behaviors. Index Terms--Dynamic load models, load modeling, measurement-based approach, nonlinear least-squares, parameter estimation.

The implementation of a continuously-controlled reactive compensation device, such as an SVC or a 'static condenser' (STATCON), in a distribution-level substation provides opportunities to improve power quality and reliability due to the speed of response of such a device. Further benefits can be gained by coordinating the reactive compensation device and its related controls with other substation voltage control equipment, such as load tap changing (LTC) transformers and mechanically-switched capacitors. The results presented in this paper illustrate the impact that a + or - 12 Mvar STATCON can have on a 150 MW, 12.5 kV load bus, in the Commonwealth Edison power system. Three control concepts for various levels of integration of the substation STATCON, LTCs, and mechanically-switched capacitors are presented. With broader application of SVCs and STATCONs at distribution substations, various other control strategies may also evolve.

Chaotic behaviors has been observed in computer simulations for a simple power system over a range of loading conditions. The existence of the chaos, also called strange attractor, is confirmed by calculation of its Lyapunov exponents and by its broad-band spectrum. Some implications of this analysis are also included.

The Transient Energy Function (TEF) method is a direct method of power system transient stability analysis. While research work on the subject continues, questions have been raised regarding potential applications of the method for on-line dynamic security analysis (DSA). This paper investigates some of the problems and suggests solutions for use of TEF in DSA, based on tests using real utility data. The test cases were provided by Public Service Electric and Gas Company (PSE&G). A pre-release version of a TEF program called DIRECT (version 2.9) was used. The tests indicate that TEF does have a place in DSA in conjunction with other available DSA methods.

Accurate load modeling is essential for power system dynamic simulation. In this paper, four dynamic load models are identified based on multiple online measurement data from the Taiwan Power System. The performances in modeling real and reactive power behaviors by dynamic and selected static load models are evaluated. Parameter variation with respect to different loading conditions is analyzed. A simple and efficient method is presented to estimate a representative parameter set for different loading conditions. The cross-validation technique is applied to validate the four dynamic load models in order to obtain a better estimate of their performance. Numerical studies indicate that linear dynamic load models studied in this paper give better results than two nonlinear dynamic load models in modeling reactive power behaviors during disturbance while they are comparable in modeling real power behaviors. [ABSTRACT FROM AUTHOR]